Purification process



Patented July 3, 1934 UNITED STATES PURIFICATION PROCESS George Chandler Cox, Carteret, N. J., and Henry K. McIntyre, deceased, late of State College Station, Raleigh, N. 0.,

by Edna Moore McIntyre,

State College Station, Raleigh, N. 0., and Malcolm McIntyre, Cranford, N. J., executors No Drawing. Original application September 4,

1924, Serial N 0.

735,833, now Patent No.

1,849,749, dated March 15, 1932. Divided and this application November 18, 1931, Serial No.

3 Claims.

This invention relates to the purification of compounds of the metallic elements by the electrolytic removal of the undesired impurity while such metallic compounds are in the fused state.

Various impurities occur in the compounds of the metallic elements which it has been found can sometimes be removed more economically by the proposed method than by existing chemical methods.

The impurities may be compounds of the metallic elements or compounds of the non-metallic elements. By way of illustration the following groups of the periodic arrangement of the elements may be listed. In the alkali and alkaline earth groups of the elements the various natural compounds and often the technically prepared compounds of these elements contain impurities of aluminum, silicon and the base metals, iron, nickel, etc. In group three, the earth group, and group four of the periodic table beginning with aluminum and titanium respectively the various natural compounds and sometimes the technically prepared compounds of these elements contain impurities of non-metallic elements, such as silicon and phosphorus, etc., and

the base metals.

The purpose of this process is to purify, while in the fused state, the compounds of the metallic elements, by removing electrolytically those impurities of either metallic or non-metallic compounds which have a lower decomposition electromotive force than the metallic compound to be purified.

Another object of the process is to provide a means whereby the fused compounds are maintained at the optimum conditions required for the purification even though the fusion point rises as the impurities are removed.

The process comprises broadly the supplying of heat energy to the electrolyte by generating heat within the electrolyte, it being found impractical with many metallic compounds to supply sufiicient heat through the refractory materials to the electrolyte to carry the process to a conclusion, direct current being passed through the electrolyte to bring about the electrolytic ac- .tion and the reduction of the undesired element from its compound or compounds.

While other ways of supplying heat, to the electrolyte, may suggest themselves to one skilled in the art, it is proposed to supply this heat by means of electric current. This current may be alternating current to supply heat energy to the electrolyte by means of electrodes within the electrolyte chamber, which electrodes may be in contact with or below the surface of the electrolyte or they may, during operation, be slightly above the surface of 'the electrolyte, to cause an arc to be formed therebetween. If preferred, the energy may be furnished by an induction winding which, with or without a core is so disposed as to generate heat within the electrolyte.

If preferred, any two or more or all of the methods of heating the electrolyte may be used in the same furnace and under some conditions, it may be found to be desirable to use one or more forms during part of the operation and one or more of the same or others during another part of the operation for different conditions.

The direct current or electrolytic electrodes are preferably entirely independent of the alternating current electrodes or other heating means and are preferably arranged-so the path of the direct current will be at a decided angle to the path of any conducted or induced heating current.

In operation, the electrolyte is maintained at sufficient temperature by the heating means and the direct current turned on to bring about electrolysis. The voltage of this direct current is maintained at such a point as will insure the reduction of the compound which it is desired to remove from the metallic compound.

The electro-positive element or radical reduced from compound which forms the impurity of the metallic compound will collect at the cathode while the other portion of the compound will collect adjacent the anode.

The position of thecathode and anode in the furnace and their relative positions to each other and to the heating current electrodes, if such are used, depends upon the impurity or impurities to be removed from the metallic compound.

This application is a division of application filed September 4, 1924, Patent No. 1,849,749.

Various modifications and details will be evident to one skilled in the art and it is to be understood that the invention is not intended to be limited to details and that various changes and modifications may be made without departing from the spirit of the invention and within the scope of the appended claims.

Having described the invention, what is claimed and desired to have secured by Letters Patent 1s:-

1. The process of purifying metallic compounds which comprises the maintaining of the impure compounds at the optimum conditions to reduce the impurities without reduction of the compound to be purified, by the generation of heat within the electrolyte and the passing of direct current through the electrolyte, thereby reducing and depositing the undesired element or elements at the cathode and leaving the electrolyte in a purer state.

2. The process of purifying metallic compounds which comprises the maintaining of impure compounds at the optimum conditions to reduce the compounds at one set of optimum conditions to reduce one or more impurities without reduction of the compound being purified, by the generation of heat within the electrolyte and by the passing of direct current through the electrolyte, and by then altering the optimum conditions to reduce another impurity without reduction of the compound, thereby reducing and depositing the desired element or elements at the cathode and leaving the electrolyte in a purer state.

GEORGE CHANDLER COX. MALCOLM McINTYRE, Joint Executor of the last will and testament of Henry K. McIntyre, deceased.

EDNA MOORE McINTYRE, Joint Executrix of the last will and testament of Henry K. McIntyre, deceased. 

